Building APIs with Django and Django Rest Framework

53 Pages·2017·0.96 MB·English

Building APIs with Django and Django
Rest Framework
Release 2.0
Agiliq
Aug 07, 2021

Contents
1 Introductions 3
1.1 Whoisthisbookfor? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Howtoreadthisbook? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 Setup,ModelsandAdmin 5
2.1 Creatingaproject . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Databasesetup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.3 Creatingmodels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Activatingmodels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3 AsimpleAPIwithpureDjango 9
3.1 TheendpointsandtheURLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Connectingurlstotheviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.3 Writingtheviews. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 UsingtheAPI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.5 WhydoweneedDRF?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4 SerializingandDeserializingData 13
4.1 SerializationandDeserialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2 CreatingSerializers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.3 ThePollSerializerindetail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.4 UsingthePollSerializer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5 ViewsandGenericViews 17
5.1 CreatingViewswithAPIView . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.2 UsingDRFgenericviewstosimplifycode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.3 Moregenericviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.4 NextSteps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6 Moreviewsandviewsets 25
6.1 AbetterURLstructure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
6.2 Changingtheviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
6.3 IntroducingViewsetsandRouters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.4 Choosingthebaseclasstouse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.5 Nextsteps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
7 AccessControl 31
i
7.1 Creatingauser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
7.2 Authenticationschemesetup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
7.3 TheloginAPI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
7.4 Finegrainedaccesscontrol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
7.5 Nextsteps: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
8 TestingandContinuousIntegeration 37
8.1 CreatingTestRequests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
8.2 TestingAPIswithauthentication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
8.3 UsingAPIClient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
8.4 .postandcreate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8.5 ContinuousintegrationwithCircleCI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8.6 SettingupCircleCI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8.7 Writingcircleconfigurationfile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
9 Appendix 45
9.1 TestingandUsingAPIwithPostman . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.2 DocumentingAPIs(withSwaggerandmore) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
ii
BuildingAPIswithDjangoandDjangoRestFramework,Release2.0
BuildingAPIswithDjangoandDRFtakesoverwheretheDjangotutorialsstop. IntheDjangotutorials,youbuilta
regularDjangopollsapp. WewillrebuildanAPIforasimilarapp.
In the chapters to come, we will build a REST(ish) api with authorization, rate limiting, first with pure Django and
thenwithDRF.Wewillcovertesting,continuousintegration,documentationtoolsandAPIcollaborationtools.
Chapters:
Contents 1
BuildingAPIswithDjangoandDjangoRestFramework,Release2.0
2 Contents
1
CHAPTER
Introductions
BuildingAPIswithDjangoandDjangoRestFrameworkstartswheretheDjango“Polls”tutorialstops,andtakesyou
throughbuildingthepollsapp,butthistimeusingAPIs.YouwilllearnthebasicsofDjangoRestFrameworkincluding
serialization, views, generic views, viewsets, testing, access control. You will also learn about API documentation
usingswaggerandraml.
1.1 Who is this book for?
IfyouhavefinishedtheDjango“Polls”tutorial, andwanttolearnusingDRFtobuildAPIs, thisbookisperfectfor
you. ThisbookassumessomeknowledgeofDjangoandPython,whichyoushouldhavebuiltifyouhavefinishedthe
“Poll”turtorial. NoexistingknowledgeofDRFisassumed.
1.2 How to read this book?
The chapters are meant to be read in order. If you have existing knowledge of some chapters, you can quickly go
throughthatchapter,butIhighlyrecommendreadingtheminorderaseachchapterbuildsontheprevious.
3
BuildingAPIswithDjangoandDjangoRestFramework,Release2.0
4 Chapter1. Introductions
2
CHAPTER
Setup, Models and Admin
InthistutorialwewillwalkthroughaprocessofcreatinganAPIforabasicpollapplication. WewillbeusingPython
3.6.x,Django2.0.xandDjangoRestFramework3.7.xforcreatingAPI.
Firstthingsfirst,let’sinstalltherequiredmoduleswithinavirtualenvironment.
mkvirtualenv pollsapi
pip install Django
pip install djangorestframework
2.1 Creating a project
Earliestinorder,tocreateaprojectweshouldmovetothedirectorywherewewouldliketostoreourcode. Forthis
gotocommandlineandusecdcommand. Thentriggerthestartprojectcommand.
django-admin startproject pollsapi
Thiscommandgivesusa‘pollsapi’directoy. Thecontentsofthisdirectorylooklikethis:
manage.py
pollsapi/
__init__.py
settings.py
urls.py
wsgi.py
2.2 Database setup
We will use SQlite database, which is already included with Python. The pollsapi/settings.py file would
alreadyhavethecorrectsettings.
5
BuildingAPIswithDjangoandDjangoRestFramework,Release2.0
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
}
}
Now, use the migrate command which builds the needed database tables in regard to the django_pollsapi/
settings.pyfile.
python manage.py migrate
2.3 Creating models
Beforecreatingourdatabasemodels,letuscreateourpollsapiApp.
python manage.py startapp polls
Theabovecommandresultsina‘polls’directorycontainingdifferentfiles:
admin.py
apps.py
models.py
tests.py
views.py
Stepinto‘models.py’fileandstartwritingthemodels.ForcreatingthepollsapiwearegoingtocreateaPollmodel,
aChoicemodelandaVotemodel. Oncewearedonewithdesigningourmodels,themodels.pyfileshouldlook
likethis:
ThesemodelsarethesameasyouwouldhaveseenintheDjangointroductiontutorial.
from django.db import models
from django.contrib.auth.models import User
class Poll(models.Model):
question = models.CharField(max_length=100)
created_by = models.ForeignKey(User, on_delete=models.CASCADE)
pub_date = models.DateTimeField(auto_now=True)
def __str__(self):
return self.question
class Choice(models.Model):
poll = models.ForeignKey(Poll, related_name='choices', on_delete=models.CASCADE)
choice_text = models.CharField(max_length=100)
def __str__(self):
return self.choice_text
class Vote(models.Model):
choice = models.ForeignKey(Choice, related_name='votes', on_delete=models.CASCADE)
(continuesonnextpage)
6 Chapter2. Setup,ModelsandAdmin